Temperature and volume control valve assembly

ABSTRACT

A mixing valve (10) has a modular cartridge (60) rotatably mounted in housing (12). The cartridge has a bottom volume control valve plate (58) attached to a lower section (62) housing a pressure balance valve (80). The lower section (62) is secured to an upper section (120) that rotatably receives a temperature control plate (150). The plates (58) and (150) are both rotatable about a common axis (64). The plate (58) is controlled by operation of stem (180) attached to handle (34). The plate (150) is controlled by stem (160) which is operated by knob (38). An insert (250) allows the knob (38) to operate even when hot and cold water supplies are inverted. A splined hot water stop ring (228) sits in handle (34) and adaptably limits rotation of knob (38) for a selected maximum water temperature. Outer seals (58) assure that all water flows through cartridge (60) when the volume is set for partial flow.

TECHNICAL FIELD

The present invention relates to mixing valves for tub spouts and showerheads and more particularly to pressure balanced, volume controlled andtemperature controlled mixing valves.

BACKGROUND OF THE INVENTION

Single handle mixing valves have beccme commonplace in today's plumbingmarket. However, many compromises have been built into mixing valvessuch as the compromise between large flow rates and easy temperaturecontrol. Furthermore, mixing valves are often built without pressurebalance valves. Previous mixing valves that have been designed with abuilt-in pressure balance mechanism are bulky and not adequatelypackaged in a compact housing. However, lack of a pressure balance valvecan result in rapid change of water temperature when either the hotwater supply or the cold water supply pressure drops. The pressure dropcan occur if another faucet, dishwasher, or washing machine is turnedon, or a toilet is flushed. When either the cold or hot water supplypressure changes, discomfort can result if a person is taking a shower.

Furthermore, previous pressure balance valves have been complicatedmechanisms that cannot be easily repaired or have its parts replaced.

What is needed is an easily assembled cartridge type mixing valveassembly which pressure balances the hot and cold water supply andprovides full adjustment of the volume and temperature in a compactmixing valve housing having easily adjusted volume and temperaturecontrols which work in the same fashion whether the hot and cold watersupplies are attached to the mixing valve body in a normal or reversedfashion.

What is needed is a mixing valve that has its valve mechanisms housed ina cartridge that can be easily replaced when necessary.

SUMMARY OF THE INVENTION

In accordance with one aspect of the invention, the mixing valve forfluids includes a housing having a cavity with the first and secondsupply ports and a discharge port in communication with the cavity. Thecavity receives a cartridge that is rotatably mounted in the housing ona longitudinal axis. The cartridge has a first generally planar valvingsurface substantially perpendicular to the axis of rotation sealinglyabutting two supply ports for controlling volume flow through tworespective inlets of the cartridge. The cartridge has intermediate firstand second ports downstream in communication with the respective inlets.A second generally planar valving surface is slidably movable within thecartridge over the intermediate ports for controlling the relativeproportion of the fluid flow from the two intermediate ports.Preferably, the second valving surface moves in a rotatable fashionabout a longitudinal axis which preferably is the same axis about whichthe first valving surface rotates.

A first operating device controls the rotated position of the cartridgeand consequently the first planar valving surface. A second operatingdevice preferably rotates the second planar valving surface relative tothe cartridge for adjusting the relative proportion of fluid flow fromthe first and second intermediate ports. Preferably a pressure balancemechanism is interposed between the first valving surface and theintermediate ports and is rotationally fixed within the cartridge sothat it rotates with the cartridge within the cavity.

According to another aspect of the invention, inner seals are interposedbetween the respective supply ports and the first planar valving surfaceof the cartridge. An outer sealing means is interposed between thehousing and the first valving surface and is operatively interposedbetween the supply ports and the discharge port and is spaced about theinner seals such that when the first valving surface is rotated topartially uncover the supply ports, the outer seal prevents fluid flowdirectly from the supply ports to the discharge port thereby preventingany fluid from bypassing the intermediate first and second ports so thatall water must pass through the cartridge. Preferably the outer sealincludes two annular rings that are positioned about the respectiveinner seals. The outer annular seals have a diameter sufficiently largeto be spaced from the inner seals the diameter of the inlets through thefirst planar valving surface.

According to another aspect of the invention, the mixing valve has avolume control which is rotatable about the same longitudinal axis ofrotation of the first planar valving surface and rotates the cartridgeincluding the first valving surface. A temperature control knob is alsomounted for rotation about the same longitudinal axis and controls therotational position of the temperature adjustment valve surface. Therotatable knob has an interior stop shoulder for limiting rotationalmovement of the knob. The stop shoulder, when in the cold position,abuts a fixed shoulder in a seat within the volume control handle, andwhen in the adjusted hot position abuts an arcuate stop member which isadjustable to a variety of fixed positions adjacent the arcuate outerperiphery of the seat within the volume control handle.

According to another aspect of the invention, the temperature controlknob is mounted on an operating stem that is connected to a secondvalving surface for adjusting the temperature of the water with anorienting insert interposed between the operating stem and thetemperature control knob to orient the knob with respect to the housingsuch that the knob is in a first position and moved to a second positionto control the water flow from a cold temperature to an adjusted hottemperature independent of whether the first supply port is connected toa cold water supply and the second supply port is connected to a hotwater supply or vice versa. Preferably the stem is radially asymmetricand the orienting insert has a socket complementarily shaped to receivethe stem and the knob has a socket shaped to receive the orientinginsert in the first or second rotated position. In addition, a positiveengagement is integrally connected to the orienting insert to allow itto be mounted within the temperature control knob in only the firstposition when the hot and cold water supplies are normally positioned.The positive engagement is also removable to allow the orienting insertto be positioned in the second rotated position when the hot and oldwater supplies are in an inverted or reversed position. In this way thetemperature control knob maintains its same orientation and is rotatedin the same direction and the same amount whether the hot and cold watersupplies are normally positioned or inverted.

The combination of an adjustable stop member, the orienting insert, acartridge assembly that houses the pressure balance mechanism having tworotational valving surfaces, one for volume control and a second withinthe cartridge for temperature adjustment, provides for an easilyoperated, compactly built, and consistently worked mixing valve thatdoes not compromise on volume flow, temperature adjustment, ease ofoperation, ease of installation, and compensation for sudden pressurechanges.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference will now be made to the accompanying drawings in which

FIG. 1 is a perspective view of a mixing valve assembly according to theinvention;

FIG. 2 is an elevational, segmented view of the valve assembly shown inFIG. 1;

FIG. 3 is a top plan view of the valve housing member;

FIG. 4 is a fragmentary, bottom perspective view of the lower portion ofthe cartridge;

FIG. 5 is an exploded top perspective view of the cartridge, itsinterior members, valve stems and seals, and housing cap;

FIG. 6 is a fragmentary, cross-sectional view taken along the lines 6--6in FIG. 2 with the volume control plate rotated to a partial onposition;

FIG. 7 is an exploded top perspective view of the lower cartridgesection and its interior parts;

FIG. 8 is a cross-sectional view of the cartridge taken along the lines8--8 shown in FIG. 2 with the temperature control valve plate in anintermediate position;

FIG. 9 is a view similar to FIG. 8 with the temperature control valveplate rotated to the cold position;

FIG. 10 is a cross-sectional view taken along the lines 10--10 in FIG.2;

FIG. 11 is an exploded perspective and partially segmented view of themixing valve illustrating the volume control handle, temperature controlknob and their mounting on the respective stems of the mixing valve;

FIG. 12 is a cross sectional view taken along the lines 12--12 shown inFIG. 2 with the temperature control knob rotated to the cold position;

FIG. 13 is a view similar to FIG. 12 with the hot water stop memberadjusted for a lowered maximum water temperature and the temperaturecontrol knob rotated to the maximum hot position against the stopmember;

FIG. 14 is an exploded view of the temperature control knob andorienting insert;

FIG. 15 is a bottom plan view of the temperature control knob with theorienting insert in the standard configuration;

FIG. 16 is a view similar to FIG. 15 with the orienting insert in thetemperature control knob in its inverted position; and

FIG. 17 is a side elevation and partially segmented view of an alternateembodiment of the upper cartridge section and volume control stem.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to FIG. 1, mixing valve 10 has a housing 12 connected tofitting 14 which is usually mounted behind a shower wall 16. The fitting14 has a cold water supply nipple 18 and a hot water supply nipple 20,and outlet nipple 22 leading to a tub spout (not shown) or outlet nipple24 connected to a shower riser (not shown). Outlet nipple 24 is in fluidcommunication with outlet nipple 22. The body has a cosmetic collar 26which is mounted as shown in FIG. 2 via a friction sealing ring 28 thatis fitted in a groove 30 in housing 12. A collar 32 threadably engagesthe housing 12. A volume control handle 34 having a lever 36 isrotatable about a central longitudinal axis 64 through housing 12.Temperature control knob 38 is also rotatably mounted at the outerdistal end of the volume control handle 34 and is rotatable about thesame longitudinal axis 64. Knob 38 can also be referred to as a handle.

The internal valving is more clearly shown in FIGS. 2-10. For simplicityof reference, the temperature control knob 38 is located at the top ofthe mixing valve as illustrated in FIG. 2. All reference to top, bottom,upper and lower is made in reference to FIG. 2 even though its perfectlyacceptable to mount the mixing valve in other orientations asillustrated in FIG. 1. Referring now to FIGS. 2 and 3, the housing 12has a cavity 40 with a supply port 42 in communication with a watersupply through nipple 18 and supply port 44 in communication with awater supply through nipple 20. The supply ports 42 and 44 pass throughan end axial positioned wall 44 at the bottom of the cavity 40 and facesthe open end 41 thereof. As shown in FIG. 2, inner sealing elements 46are mounted in counterbores 48 of the two ports 42 and 44. A dischargeport 50 also extends through the axially positioned wall 45 and incommunication with the two outlet nipples 22 and 24.

Two outer sealing rings 52 are fitted into annular grooves 54 in thewall 45 and are positioned about the inner sealing elements 46 such thatthe outer sealing rings 52 are interposed between the ports 42 and 44and discharge port 50. The outer sealing elements 52 are spaced from theinner sealing elements 46 substantially the diameter of the inlets 56through a volume control valve plate 58.

The volume control valve plate, made from stainless steel, is affixedagainst rotation to a cartridge assembly 60 which is rotated by handle34 as described later. The handle 34 as it rotates about axis 62 alsorotates the cartridge about the longitudinal axis 62 such that thevolume control plate 58 also rotates about an axis 62 such that inlets56 can become fully aligned with supply ports 42 as shown in FIG. 2 atthe full on position or can be closed to a full off position.Furthermore in the intermediate partially on position between the fullon and full off, outer seals prevent any water about inner seal 46 fromreaching discharge port 50 without first passing through the cartridge60 as explained below. In addition, cross flow between ports 42 and 44is prevented. The outer sealing elements 52 effectively prevent waterfrom bypassing cartridge assembly 60 is illustrated in FIG. 6.

As shown in FIGS. 4 and 5, cartridge assembly 60 has a lower section 62with two bottom end flanges 66 that have notches 68. A lateral groove 69is spaced above notch 68 so that a retaining lip 71 is formedtherebetween. The notches 68 receive corresponding tabs 70 in the volumecontrol valve plate 58 to rotationally affix the volume control valveplate 58 to the cartridge assembly 60. The distal ends 73 of tabs 70 arebent upward and inward to be received in groove 69 so that the plate 58is retained on section 62 via lips 71. As shown in FIG. 2, appropriateseal rings 72 are interposed between each inlet 56 and the valve housinglower section 62 to prevent leaking therebetween.

Referring now to FIG. 7, the lower section 62 has passages 74a and 74bleading to a first section 76 and second section 78, respectively, of aspool type pressure balance proportioning valve 80. The spool type valve80 has an outer spool 82 with five sealing rings 84 about its outercircumference to fluidically seal passage 74a and passage 74b. The outerspool 82 has axially spaced apertures 86, 88, 90 and 92 aligned with therespective passages 74b, 75b, 75a and 74a. A sliding piston 94 also hasapertures 96 therethrough which communicates sections 76 and 78 withrespective grooves 98 and 99 which are in selective communication withthe passages 74a, 74b and 75a and 75b via the apertures 86, 88, 90 and92 in the outer spool. In this way the pressure within each passage 75aand 75b is substantially equalized via the movement of piston 94 of thespool type valve 80.

The lower section 62, for ease in manufacturing, is made from two halves100 and 102 with each half having a flange 104 and 105 that has anaperture 108 and 109 that receives a threaded fastener 110 which issecured to the threaded apertures 111 and 112 in the flanges 113 and114. Each half 100 and 102 has a cavity 116 and 118 sized to receivehalf of outer spool 82. Each half has a pair of laterally extendingprongs 119 which snap fittingly are received into apertures 122 in alower flange 124 of an upper cartridge section 120 as shown in FIG. 4.

Referring back to FIGS. 2 and 5, a gasket 126 has two apertures 128a and128b in communication with passages 75a and 75b, respectively. The topportion of lower section 62 has a contoured shoulder 129 that receives alower flange 131 of an intermediate cartridge section 130. The cartridgesection 130 has two intermediate ports 132 and 134 therethrough incommunication with respect to passages 75a and 75b. The gasket 126prevents cross flow between the passages 75a and 75b. Two sealingelements 136 identical to sealing elements 46 are placed within theintermediate cartridge member 130. The upper end 138 of the intermediatecartridge member 130 abuts against an annular radially extendingshoulder 140 in the upper cartridge section 120. A reduced diametersection 142 provides a mixing chamber 144 wherein the temperaturecontrol valve plate 150 is seated. The temperature control valve plate150 has a valving surface with a crescent aperture 152 therethrough andan undercut 154 which allows the mixing of water therein. The crescentaperture 152 extends substantially over one hundred and eighty (180)degrees radially about the control valve plate 150. A supporting rib 156extends within the undercut 154 to the outer periphery 157 of thetemperature control valve plate 150. More than one rib 156 may beemployed and circumferentially spaced about plate 150.

The temperature control valve plate 150 fits within reduced diametersection 142 of the upper cartridge section 140. The intermediatecartridge member 130 fits within larger lower section 162 of cartridgesection 120. The plate 150 and member 130 are inserted from the lowerend of the upper cartridge section 120. The upper end of the uppercartridge section 140 has a radially extending inner flange 164 toprevent the temperature control valve plate 150 from exiting through thetop end 166. The gasket 126 is then seated Within lower flange 131 ofmember 130 and the lower section 62 is snap fitted in place to uppersection 140. Valve plate 58 is mounted within key notches 68 to form themodular cartridge assembly 60.

As shown in FIGS. 2, 8 and 9, the outer periphery 157 of valve plate 150is sized to provide an annular clearance or passage 170 clearance withthe reduced diameter section 142. The passage 170 is in communicationwith a discharge outlet 172 formed between the upper section 120 andlower section 62 of the cartridge assembly 60 as shown in FIG. 4. Thedischarge outlet 172 is in communication with the discharge port 50 viaan annular chamber 177 formed about the lower section 62 within thecavity 40. Discharge port 50 is in fluid communication with outletnipples 22 and 24 of fitting 14 in a conventional manner.

The cartridge 60 is fitted within the open distal end 41 of cavity 40 sothat plate 58 lays flat against seals 46 and 52. Referring back to FIGS.2 and 5, an operating stem 160 is then positioned in seat 159 via itscomplementary shaped mating section 161. The seat 159 and section 161may have rotationally asymmetric shapes or an eccentric pin and holearrangement may be used to assure that stem 160 has only one orientationwith respect to seat 159. An O-ring 173 is fitted within groove 174 ofstem 160. The stem 160 also has a rounded seat section 176. An annularvolume control stem 180 is then slipped over stem 160 via its centralopening 182 and is in sealing engagement via sealing O-ring 173 toprevent leakage therebetween. The seat section 176 rotatably seats inrecessed seat 186 of stem 180 for allowing relative rotation of thevolume control stem 180 with the temperature control stem 160. Thetemperature control stem 160 is longer than stem 180 so that it extendsbeyond the upper end 184 of stem 180. The stem 180 has a radiallyextending key 188 which fits within notch 167 in upper end 166 of theupper cartridge section 120. Rotation of stem 180 rotates the cartridgeassembly 60. A sealing ring 192 fits within groove 189 about the stem180.

In an alternate embodiment as shown in FIG. 17, the upper section 120and volume control stem may be made as an integral upper cartridge andvolume control stem member 320. Member 320 has rib 309 at reduceddiameter section 342. The volume control stem section 360 has a threadedsection 321, seat section 316, and groove 389 that receives seal 192.The temperature control stem 160 is mounted from lower end 324 that hasaperture 322 that receives lower cartridge section 62 and extendsthrough aperture 384. Use of member 320 will form a cartridge assemblythat includes a volume control stem and a temperature control stem.

A housing cap 190 is then placed over the cartridge assembly 60. Thehousing cap 190 has an upper inwardly extending flange 206 and a centralaperture 208 therethrough to allow the volume control stem 180 andtemperature control stem 160 to extend therethrough. The O-ring 192seals aperture 208 against leakage. The cap 190 has a lower sealingflange 194 which seats an O-ring 196 and has an outer flat seatingflange 198 that has a key 199 that fits within a slot 201 at the opendistal end 41 of the housing 12 as shown in FIG. 11. The housing 12 hasa threaded section 203 which threadably secures the collar 32. Thecollar 32 has an inner flange 204 which abuts against the flange 198 ofthe cap 190 to secure the cap in place. Securement of the cap 190 inplace maintains the cartridge 60, volume control stem 180, andtemperature control stem 160 in an integrated assembled unit as shown inFIGS. 2 and 11. Seal 196 prevents leakage between the housing 12 and cap190.

As shown in FIG. 10, the cap 190 also has two internal longitudinalshoulders 210 and 212 which are about 90 degrees apart and aredimensioned to engage key 188 in the volume control stem 180 and analigned rib 209 of upper cartridge section 120. A shoulder 211 isradially placed inward to interfere with rib 209 and key 188 so that thecap 190 cannot be incorrectly placed over cartridge 60 and to assure rib209 and key 188 are between shoulders 210 and 212.

As shown in FIGS. 2 and 11, the stem 180 is rotated by handle 34 whichhas an asymmetric opening 214 shaped to snugly receive a complementaryshaped section 216 of stem 180. A lock nut 218 can then be threaded ontothe threaded section 220 of stem 180 to secure the handle 134 onto stem180.

The handle 34 has an upper section with a seat 222 with a splinedsection 224 thereabout and an axially extending stop shoulder 226. A rib227 radially extends inward from shoulder 226. An arcuate hot water stopring 228 has a complementary splined section 230 which can adjustably bepositioned and secured to the splined section 224 about a number ofrotated positions. The ring 228 has a stop shoulder 232 and arcuate rib236. The ring 228 abuts against rib 227 to be frictionally engaged inplace in seat 222.

As shown in FIGS. 11-13, the stem 160 receives the temperature controlknob 38 such that its stop shoulder 238 can rotate between the shoulder226 on handle 34 and the stop shoulder 232 on member 228. A screw 240threads into a hole 242 in stem 160 to secure the temperature controlknob thereon. A cosmetic cap 244 fits within a recess 246 in temperaturecontrol knob 38.

Referring to FIG. 14, the temperature control knob 38 has an orientinginsert 250 which fits within a lower recess 252 in the temperaturecontrol knob 38. A hole 254 extends axially above the recess 252. Theinsert 250 has a protrusion 256 which is positioned to be receivedwithin the hole 254. The insert 250 has a symmetrical shape so that itcan be rotated 180 degrees with its prong 256 removed and positionedback into recess 252. The insert 250 has a rotatably asymmetricalaperture 258 which is D-shaped to fit onto the D-shaped temperaturecontrol stem 160 in one rotated position only. The aperture 258 does notextend all the way through insert 250. Only a smaller screw hole 259extends through insert 250 so that insert 250 cannot be mounted upsidedown on stem 160.

Operation of the Valve

The valve cartridge 60 can be rotated to an off position such that thevalve plate 58 has its inlets 56 totally misaligned with the supplyports 42 and 44 such that the inner seal elements 46 abut against theplate 58 and no water flows past the seals 46. When in the off position,the key 188 and rib 209 of cartridge section 120 abut rib 210 of cap190. The handle 34 can be rotated counterclockwise so that the cartridge60 is rotated away from rib 210 to any position up until key 188 and rib209 abut rib 210 as shown in FIG. 10. The inlets 56 can be selectivelypartially aligned such as shown in FIG. 6 or can be fully aligned asshown in FIG. 2 with the supply ports 42 and 44. The inlets 56 are thesame size and are positioned to provide the same amount of partialalignment simultaneously with respect to ports 42 and 44. In addition,during partial alignment, an outer sealing element 52 provide that allwater passes through inlets 56 and prevents any water passing under theplate 58 directly to the discharge port 50 and prevents cross flowbetween ports 42 and 44.

Once the valve is open, cold and hot water, respectively, flow throughpassages 74a and 74b to the appropriate apertures 86 and 92 within spool82. The water pressure within the two supply lines act upon the piston94 to even the flow rate of the hot and cold water passing to thepassages 75a and 75b via apertures 90 and 88, respectively. The waterthen flows to intermediate ports 132 and 134. Intermediate port 132 incommunication with supply port 42 normally supplies cold water andintermediate port 134 in communication with supply port 44 normallysupplies hot water. Flow past the intermediate ports 132 and 134 iscontrolled by the position of the temperature control valve plate 150which can be rotated from a full cold position as shown in FIG. 9 withtemperature control knob having its stop shoulder abutting stop shoulder226 in the volume control handle 34 as shown in FIG. 12 counterclockwiseso that the stop shoulder 238 now can abut stop 232 of arcuate member228.

FIG. 8 discloses the temperature control valve plate in an intermediateposition where it allows equal amounts of hot and cold water from theports 132 and 134, respectively, via crescent aperture 152 in plate 150.Water is then mixed within the mixing chamber 144 and passes about theouter periphery 157 in passage 170 down through cartridge outlet 172.The water then flows about the lower section 62 through annular chamber177 within the cavity 40 to the discharge port 50 at the end wall of thehousing 12. Water then flows from discharge port 50 to the fitting 14through either outlet nipple 22 or 24 if water is being directed to thetub spout or shower, respectively.

The maximum water temperature can be easily adjusted by removing cap 244and unscrewing screw 240 so that temperature knob 38 is removed. The hotwater stop ring 228 can then be removed, rotated and reinserted in thesplined section 234 of handle 34. The splines 224 are sized such thatrotation of the ring member 228 one notch or one spline will reduce themaximum water temperature approximately 2 degrees Fahrenheit. Theposition of ring 228 as shown in FIG. 13 reduces the counterclockwiserotation of the control knob 228 as compared to FIG. 12. Thus themaximum temperature of the water is also reduced. The adjustment of themaximum hot water temperature allowed via ring 228 can be achievedwithout shutting off the water supply to the housing 12 or majordisassembly of the mixing valve 10.

Because the temperature control valve plate 150 is carried within thecartridge 60, rotation of the cartridge 60 carries, or rotates, thetemperature control plate 150 therewith so that there is no temperaturechange as volume control handle 34 is rotated. The temperature controlhandle 38 also rotates with rotation of volume control handle 34. Thetemperature knob 38 can be independently rotated to independently movethe valve plate 150 to adjust the temperature between the cold stop rib226 and the hot stop shoulder 232 of member 228.

As described before, the normal configuration of the mixing valve is tohave cold water enter port 42 from cold water nipple 18 and hot waterentering port 44 from hot water nipple 20. It is also desirable forhaving the valve operate in the same fashion when the hot and cold watersupplies are reversed so that hot water enters the nipple 22 and goesinto supply port 42 and cold water goes through the supply nipple 20into supply port 44. In other words, it is desirable that thetemperature control knob 38 is still rotated counterclockwise from thenormal full cold position to an intermediate mix or hot position.

With the present construction, it can easily be done by again removal ofcosmetic cap 244 and removal of temperature control knob 38 byunscrewing screw 240. The stem 160 can then be rotated one hundred andeighty (180) degrees. The orienting insert 250 can then be removed fromthe temperature control knob 38. Its protrusion 256 is removed. Theinsert 250 is rotated the one hundred and eighty (180) degrees andreinserted within the recess 250. The temperature control knob 38 isthen remounted onto the stem 160. Because both the orienting insert 250and the stem 160 have been rotated one hundred and eighty (180) degrees,the knob 38 is in the same position as before with its stop shoulder 238between abutting the rib 226 of volume control handle 34 and the stoprib 232 of the hot water stop ring 228. However, the crescent 152 of thetemperature control plate 150 is initially over only intermediate port134 which now supplies cold water and rotation of it counterclockwisewill then cause the intermediate port 132 which now supplies the hotwater to gradually become uncovered while slowly covering upintermediate port 134 to adjust the temperature of the water from coldto hot as knob 38 is rotated counterclockwise.

The protrusion 256 provides for a standard orienting of insert 250 andprovides assembly only in the standard fashion with adjustment onlybeing intentionally done when the ports 44 and 42 are interchanged sothat they are supplying hot and cold water in a reverse fashion from theordinary mode. The reversed position of the insert 250 is shown in FIG.16 with the standard configuration shown in FIG. 15. The temperaturepointer 260 of the temperature control knob 38 as illustrated points tothe same place regardless of the position of orienting insert 250. Assuch, a single temperature scale 262 can be stamped, printed or decaledonto the volume control handle 34. Furthermore, the stop shoulder 238 onknob 38 is also in the same position so that the function of the knob 38appears to remain the same to an operator.

Furthermore, if pressure in the cold or hot water line suddenly drops,the pressure balance valve 80 immediately responds to the pressure dropto maintain the same relative flow rates through both inlets 56 in thevolume control valve plate. The pressure balance valve 80 preventssudden temperature changes due to pressure changes within the hot andcold water supply lines that can be caused by diversion of some of thehot or cold water.

The present invention provides for a reliable, compact, and versatilevalve assembly that has pressure balancing, volume control, andtemperature control. The mixing valve is controlled by two coaxiallymounted handles that are conveniently placed at the end of the valveassembly. Furthermore, the maximum hot water temperature which can beachieved through control of the temperature control knob can beconveniently adjusted without disassembly of the cartridge or mixingvalve housing. Furthermore, the mixing valve is suitable forback-to-back installations or other installations where the valve willreceive hot and cold water in a reverse fashion with the valve beingcapable of having the same operation in spite of the fact that the hotand cold water supplies are reversed. Furthermore, maintenance of themixing valve is easy with replacement of the modular cartridge beingavailable rather than labor intensive disassembly of all of the valveparts.

Variations and modifications of the present invention are possiblewithout departing from the spirit and scope as defined in the appendedclaims.

We claim:
 1. A mixing valve characterized by:a housing having a firstand second supply port and a discharge port; a first planar valvingsurface being rotatable about an axis perpendicular to said surface forcovering and uncovering said supply ports to control total volume ofliquid flowing from said supply ports; a first and second passagewaybeing in communication with said respective first and second supplyports when said first planar valving surface uncovers said supply portsand having their respective downstream ends forming first and secondintermediate ports that are fixed relative to said first planar valvingsurface; a second planar valving surface being generally parallel tosaid first planar valving surface and slidably movable over saidrespective first and second intermediate ports for selectivelyuncovering said intermediate ports for adjusting the relative proportionof flow therefrom; a mixed water passage downstream from said secondplanar valving surface in communication with one or both of saidintermediate ports depending on the slidable position of said secondvalving surface and directing water to said discharge port; a firstoperating means for controlling the rotated position of said firstplanar valving surface to control said total volume and for rotatingtherewith the second planar surface as said first planar surface isrotated relative to said housing; and a second operating means forsliding said second planar valving surface relative to said first planarvalving surface for adjusting the relative proportion of fluid flow fromsaid first and second intermediate ports.
 2. A mixing valve as definedin claim 1 further characterized by:said second operating meansrotatably sliding said second valving surface about an axissubstantially perpendicular to said second valving surface.
 3. A mixingvalve as defined in claim 1 further characterized by:an inner sealingmeans between said respective supply ports and said first planar valvingsurface; an outer sealing means interposed between said housing and saidfirst valving surface and operatively interposed between said supplyports and said outlet and being spaced about said inner sealing meansand spaced therefrom such that when said first valving surface isrotated to partially uncover the supply ports said outer sealing meansprevents fluid flow directly from said supply ports to said dischargeport thereby preventing fluid from bypassing said intermediate first andsecond ports.
 4. A mixing valve characterized by:a housing having acavity with two supply ports and a discharge port in communication withsaid cavity; a cartridge rotatably mounted in said housing; saidcartridge including a first generally planar valving surface sealinglyabutting said two supply ports with two inlets therethrough forcontrolling volume flow to said cartridge; said cartridge havingintermediate first and second ports downstream and in communication withsaid respective inlets; a second generally planar valving surfaceslidably movable within said cartridge over said intermediate ports forcontrolling the relative proportion of fluid flow from said twointermediate ports; operating means for rotating said cartridge withsaid first valving surface and for slidably moving said second valvingsurface within said cartridge; said cartridge having an outlet in fluidcommunication with said first and second intermediate ports and saiddischarge port in said housing.
 5. A mixing valve as defined in claim 4further characterized by:said second valving surface being substantiallyparallel to said first valving surface; and said operating meansslidably moving said second valving surface by rotating it about an axissubstantially perpendicular to said second valving surface.
 6. A mixingvalve as defined in claim 4 further characterized by:a lower and uppercartridge section being connected together; said intermediate first andsecond ports are in an intermediate cartridge member that mounts on saidlower cartridge section within said upper cartridge section; said outletbeing interposed between said upper and lower cartridge sections; and anoutlet passage in communication with said intermediate ports and saidoutlet, said outlet passage being defined in part between said uppersection and said intermediate cartridge member.
 7. A mixing valve asdefined in claim 4 further characterized by:said housing having saidcavity axially extending along said housing, said housing having an openend and a wall spaced from and facing said open end; said two supplyports positioned through said wall; said cartridge with said firstvalving surface being rotatable along an axis substantiallyperpendicular to said wall; said second generally planar valving surfacebeing substantially parallel to said wall and rotatable about said sameaxis; a cap sealingly attached to said housing; said operating meansincluding two coaxially mounted stems sealingly passing through saidcap.
 8. A mixing valve as defined in claim 4 further characterized by:aninner sealing means between said respective supply ports and said firstvalving surface for providing a sealed passage from said ports to saidfirst valving surface; an outer sealing means interposed between saidhousing and first valving surface and operatively interposed betweensaid supply ports and said discharge port and being spaced about saidinner sealing means and spaced therefrom such that when said valvingsurface is rotated to a position to partially uncover the supply ports,said outer sealing means prevents fluid flow directly from said supplyports to said discharge port thereby preventing fluid from bypassingsaid inlets and cartridge.
 9. A mixing valve as defined in claim 4further characterized by:a pressure balance means operably mounted insaid cartridge between said first valving surface and said intermediatefirst and second ports and rotatable with said cartridge for maintainingapproximately equal pressures of fluid to said intermediate first andsecond ports.
 10. A mixing valve characterized by:a housing having acavity with an open end and an axially positioned wall spaced from andfacing said open end with two supply ports therethrough; a dischargeport in communication with said cavity; a cartridge rotatably mounted insaid housing along an axis generally perpendicular to said axiallypositioned wall; said cartridge including a first generally planarvalving surface with two inlets therethrough for controlling volume flowfrom said supply ports through said inlets and into said cartridge withsaid valving surface substantially parallel to said wall; an innersealing means between said supply ports and said first valving surfacefor providing a sealed passage from said ports to said valving surface;an outer sealing means interposed between said housing and said firstvalving surface and operatively and being spaced about said innersealing means and spaced therefrom such that when said first valvingsurface is rotated to partially uncover said supply ports said outersealing means prevents fluid flow directly from said supply ports tosaid discharge port thereby preventing fluid from bypassing saidcartridge.
 11. A mixing valve as defined in claim 10 furthercharacterized by:said inner sealing means including two inner annularsealing elements having a passage therethrough and positioned in saidsupply ports; and said outer sealing means including two outer annularsealing elements positioned in an annular groove in said wall andpositioned about said respective inner annular sealing elements andfixed relative thereto.
 12. A mixing valve characterized by:a valvehousing for controlling fluid flow from two supply ports to a dischargeport; control means for controlling the proportion of fluid from saidtwo supply ports; a rotatable knob operably attached to said controlmeans; said rotatable knob having a stop shoulder means for limiting therotational movement of said knob; a seat means having an arcuateperiphery and a fixed shoulder for abutting the stop shoulder means onthe knob for limiting the rotation of the knob to a cold position; saidstop shoulder means abutable against a shoulder on an arcuate stopmember, said arcuate stop member being adjustably positioned adjacentsaid outer periphery of said seat means for adjusting the rotationallimit of said knob to a hot position; and said seat means being fixed isin a volume control handle that is movable with respect to said valvehousing.
 13. A mixing valve characterized by:a valve housing having afirst and second supply port and a mixed fluid discharge port; a valvemeans for controlling the proportion of flow from each respective supplyport to said mixed fluid discharge port by having a first positionwherein said first supply port is open and said second supply port isclosed and movable to a second position wherein said second supply portis open and said first supply port is at least partially closed; anoperating stem connected to said valve means for adjusting theproportion of flow from each respective supply port; a handle operablyconnected to said stem; limit means for limiting the movement of saidhandle with respect to said valve housing; said valve means constructedso that when fluids supplied to the respective first and second portsare interchanged said valve means can be moved such that it undergoes areverse function wherein an initial position opens said second port andcloses said first port and a final position opens said first port and atleast partially closes said second supply port; an orienting insertmeans interposed between said operating stem and said handle to orientthe handle with respect to said housing such that said handle has afirst position and is movable to a second position when said valve meansis in one of its first position and initial position and is movable toone of its second position and final position respectively; and apositive engaging means affixed to said orienting insert means andallowing said insert to be positioned with respect to said handle inonly a first position and being removable to allow said handle to bedeliberately oriented with respect to said stem and insert in analternate position.
 14. A mixing valve as defined in claim 13 furthercharacterized by:said stem being rotationally asymmetric; said orientinginsert means having a socket complementarily shaped to receive saidstem; and said handle having a socket shaped to receive said insert in afirst and second rotated position.
 15. A mixing valve as defined inclaim 14 further characterized by:said positive engaging means beingintegral with one of said insert means and said handle to allow saidhandle to receive said orientating insert in only said first rotatedposition; said positive engaging means being removable to allow saidhandle to receive said orientating insert means in either said first orsecond rotated position.
 16. A mixing valve as defined in claim 14further characterized by:said socket in said insert means not passingall the way therethrough so that said insert means cannot be mounted onsaid stem upside-down.
 17. A mixing valve as defined in claim 14 furthercharacterized by:said valve housing mounting a cartridge that housessaid valve means; said handle, stem and insert means can be adjusted totheir desired relative positions without disturbing the housing orcartridge that houses the valve means so that the fluid supply to thefirst and second supply ports need not be shut off from the mixing valvewhen adjustment of the handle, stem and orientating insert means isneeded.
 18. A rotatable modular cartridge for a mixing valve housingcharacterized by:a lower cartridge section having a first valve surfaceat an inlet end thereof for controlling flow from first and secondsupply ports in said mixing valve housing; said lower cartridge sectionhaving passage means in fluid communication with said outlet end; anupper cartridge section snap fitted to said lower cartridge section;said upper cartridge section receives a second valve surface operablymounted to said passage means; an integral upper end of said uppercartridge section defines a first operating stem on which a controlhandle is mountable for rotating said cartridge and said first valvingsurface; said first operating stem has an aperture therethrough forreceiving a second operating stem that is operably affixed to saidsecond valve surface; said cartridge has an outlet means for fluiddownstream of said second valve surface; one of said first or secondvalve surfaces operable to control total fluid flow through saidcartridge; the other of said first or second valve surfaces operable tocontrol relative proportions of fluid flow from said first and secondsupply ports in said mixing valve housing; said first valve surfaceincluding two inlets; said passage means including two passages each incommunication with a respective inlet; said first valve surface isrotatable to control total fluid flow through said cartridge; saidsecond valve surface being rotatable coaxially with respect to saidfirst valve surface and controls the relative proportion of fluid flowfrom said two passages; and said upper cartridge section defines amixing chamber therein.
 19. A rotatable modular housing as defined inclaim 18 further characterized by:said first valve surface including avalve plate having two apertures therethrough; and said valve platebeing snap fitted onto said lower cartridge section and affixed theretofor rotating therewith.
 20. A mixing valve characterized by:a valvehousing for controlling fluid flow from two supply ports to a dischargeport; control means for controlling the proportion of fluid from saidtwo supply ports; a rotatable knob operably attached to said controlmeans; said rotatable knob having a stop shoulder means for limiting therotational movement of said knob; a seat means having an arcuateperiphery and a fixed shoulder for abutting the stop shoulder means onthe knob for limiting the rotation of the knob to a cold position; saidstop shoulder means abutable against a shoulder on an arcuate stopmember; and said arcuate stop member having an outwardly facingengagement means on an outer periphery being adjustably engageable to aninner facing engagement means on the outer periphery of said seat meansfor adjusting the rotational limit of said knob to a hot position.
 21. Amixing valve as defined in claim 20 further characterized by:saidoutwardly facing engagement means includes an externally splinedperiphery on said arcuate stop member and said inner facing engagementmeans includes an internally splined seat means.
 22. A rotatable modularcartridge for a mixing valve housing characterized by:a lower cartridgesection having a first flat valve plate surface at an inlet end thereoffor controlling flow from first and second supply ports in said mixingvalve housing; said lower cartridge section having passage means influid communication with said outlet end; an upper cartridge sectionsnap fitted to said lower cartridge section; said upper cartridgesection receives a second flat valve plate surface operably mounted tosaid passage means; an integral upper end of said upper cartridgesection defines a first operating stem on which a control handle ismountable for rotating said cartridge and said first valving surface;said first operating stem has an aperture therethrough for receiving asecond operating stem that is operably affixed to said second valvesurface; said cartridge has an outlet means for fluid downstream of saidsecond valve surface; one of said first or second valve surfacesoperable to control total fluid flow through said cartridge; and theother of said first or second valve surfaces operable to controlrelative proportions of fluid flow from said first and second supplyports in said mixing valve housing.